Based on practical experience, both garlic and eggs (particularly chicken eggs) have been valued as excellent, nutritious food materials from ancient times. More recently, science has thrown light upon their composition and efficacy.
It was found around the middle of this century that the peculiar smell of garlic derives from allysine. Studies made since this discovery show that allysine is predominantly responsible for a variety of the efficacies of garlic. For example, allysine combines with vitamin B.sub.1 to form allithiamin, an activity-persistent vitamin, which functions in a similar manner to vitamin B.sub.1 and is efficiently absorbed and stored in the body to accelerate the intake of vitamin B.sub.1. It has also been reported that allysine functions to promote the secretion of acetylcholine, providing a tonic effect. Furthermore, it has been found that allysine has germ-killing or antibacterial effects and also that it combines with lipids to develop vasocleaning and hematogenous effects like vitamin E.
As to eggs, a French chemist successfully isolated phosphatidyl-choline, generally known as lecithin, from chicken egg yolk, around the middle of 19th century. Recent studies have reported that lecithin serves to improve and strengthen the brain activity. It has also been found that lecithin functions to remove LDL (low density lipoproteins: the so-called bad cholesterol) adhering to the walls of the arteries, helping to restore normal blood flow.
Thus, modern science has confirmed the efficacious effects of garlic and chicken egg yolk as nutritious foods. However, they are separately eaten in most cases and no composite foods comprised of garlic and chicken egg yolk was available. It is said that, in the southern part of Kyushu Island in Japan, a certain food made of a mixture of garlic and chicken egg yolk was produced as a food for home consumption in the feudal ages. However, the manufacture thereof was kept secret and no information was available.
Recently, interest in foods combining garlic and chicken egg yolk has increased in Japan and studies are being made regarding their preparation. Thus, a certain type of such foods is found to have been introduced in a magazine for housewives as a nutritious food which can easily be prepared at home. Besides, some such foods have been marketed commercially. The present inventor has also made an independent study to elucidate the process for preparing a composite food primarily comprised of garlic and chicken egg yolk based on the traditional technique.
The process for preparing such composite garlic-chicken egg yolk food generally includes the steps of heating and stirring garlic as a starting material to prepare a paste of garlic, mixing the paste with chicken egg yolk, and heat-treating the resultant mixture, followed by, when necessary, processing the heat-treated mixture into the form of powder or granules.
When preparing the food on a small scale at home, such steps can easily be carried out without any special contrivance or device. Even if some failure should occur and a poor product is obtained, there will be no serious problems. However, the present inventor has noticed that the simple practice of the above-mentioned steps will not produce the desired product in producing the composite food of garlic and chicken egg on a commercial scale. Several technical barriers must be overcome for production of a commercial product.
For example, for obtaining a product of high-quality substantially free of garlic smell, simple physical mixing of garlic with chicken egg yolk is not satisfactory but a sufficient chemical reaction must take place between the two components so as to form a composite product. In addition, in mass production on a commercial scale it will be necessary to reduce the repugnant garlic smell as much as possible in order to ensure for a comfortable working environment for the operators.
While the heat-treatment of a garlic-egg yolk mixture is the most important step, an ordinary heat-treatment may result in a high degree of carbonization of the mixture due to overbaking and thus the diminishment or complete loss of the efficacious ingredients,i.e. allysine and lecithine.
It should be further noted that such composite food is generally marketed in the form of a capsule with a soft capsulating material and therefore a device must be made so as to charge as much food material as possible in a unit capsule for a highly efficacious commercial food product.
It is therefore the primary object of the present invention to overcome the above-mentioned technical issues and provide a process for producing, on a mass scale, a composite food comprised of garlic and egg yolk with a high quality acceptable as a commercial food product.
While the term "egg yolk" generally refers to chicken egg yolk, it will be understood that the principle of present invention can be applied to any composite food comprised of garlic and egg yolk of other fowl such as geese or turkeys or of turtles. The term "egg yolk" as termed here includes the egg yolk of such animals.